You are the one with the false premise. Listening to too many anti-gun liars I guess.
NRA is NOT affiliated in any way with either political party. The fact that most republicans run on minimal gun control is why the NRA backs the republican party and most republican candidates. It is very simple - NRA as an organization is pro 2nd Amendment and anti gun-control for law abiding citizens. Like any individual or organization, the party that more closely matches that central view of NRA is going to receive the most of their backing. But when a democratic candidate (rare, but do exist) also run on minimal gun control, (sometimes the democrat will have a better record than his/her republican opponent) they, too, will receive the NRA's backing.
And I already said the ads were probably dishonest. I used the word probably because I have not seen them. DNC says they are lies, NRA says they are accurate. DNC has a vested interest in finding anything anti-Obama to be lies. Considering Obama's actual record (as opposed to presidential campaign rhetoric) the NRA has a vested interest in criticizing Obama on the issue of 2nd Amendment rights. Most likely neither organization is being fully honest in their evaluation of the ads.
YOU also say you have not seen them, but somehow you can make the judgment they are outright lies. How is that? By reading the Washington Post's evaluation? (a media outlet whose democratic and pro-strong gun-control are undeniable.)
I have also stated I believe truth in advertising should be applied to political ads, regardless of their origin. But threatening stations' FCC licenses, who have nothing to do with the content of the ads, is not a proper method for the parties to approach the issue of inaccurate ads. It is using threats (ie: intimidation) to repress a message they do not like.
If both parties do not like it when their opponents run inaccurate ads, then maybe they need to write a law that applies truth in advertising to political ads, instead of deliberately exempting them. But the bottom line is BOTH parties want the "right" to lie about their opponents, but also want the right to prevent their opponents from lying about them. Can't have it both ways.